POS0831 IgA VASCULITIS IN ADULTS, PEDIATRICS AND NON-VASCULITIC IgA NEPHROPATHY
Authors: S. Levanon, V. Gotlieb, Y. Kraus, I. Novofastovski, S. Brikman, A. Fawaz, M. Aghbariyya, Y. Butbul, A. Balbir-Gurman, R. Mader, A. Bieber
Journal: Annals of the Rheumatic Diseases (2022)

Background IgA vasculitis (IgAV) has been extensively studied in children, while its natural history remains poorly studied in adults. Sparse data comparing childhood and adult-onset disease has shown significant differences in their clinical presentation, especially in the severity of renal involvement, which accounts for the major long-term morbidity. IgAV shares similar renal histologic features with IgA nephropathy (IgAN), while clinically IgAN is a chronic kidney disease which may lead to end stage renal disease and dialysis. The extent of kidney injury among adults with IgAV is still a matter of uncertainty. Objectives We aimed to evaluate clinical manifestations, laboratory data, treatment patterns and long-term outcomes of pediatric and adult-onset IgAV in comparison to IgAN. Methods This retrospective collaborative study examined medical records of adults and children with IgAV and IgAN adult patients admitted to rheumatology clinic and in hospital pediatric departments in a 13-year period (2007-2019). Diagnosis of adults with IgAV relied on the Ankara criteria and was confirmed by a consistent skin biopsy with positive IgA staining by immunofluorescence. Children with IgAV were included in our study on a clinical basis. All IgAN patients had a kidney biopsy proven disease. We analyzed and compared frequencies of clinical manifestations, laboratory findings, treatment regimens and long-term outcomes at one year follow-up. Finally, we assessed long term outcomes, such as time to dialysis and all-cause mortality, till the end of the follow-up time. Results A total of 60 adult IgAV, 60 pediatric IgAV and 45 IgAN patients were included in our study. There were significantly more males in the IgAN group compared to the adult and pediatric IgAV groups (77.8%, 41.7% and 55% respectively, p=0.01). Adult IgAV patients were significantly older than IgAN patients (53.1±17.4 years vs. 45.1±15.7 years, p=0.02) and had significantly higher rates of diabetes (43.3% vs. 24.4%, p=0.05) and ischemic heart disease (18.3% vs. 4.4%, p=0.03). The pediatric IgAV group had a statistically higher rate of previous infection compared to the adult IgAV group (44.8% vs. 20%, p=0.02). At one year follow-up, IgAN patients had higher levels of serum creatinine compared to the adult IgAV group (2.002 vs. 1.100, p&lt;0.01). Data observed until the end of the follow-up time showed no difference in time to dialysis (IgAV adults: 9.8-12.4 years, IgAN: 5.0-6.6 years, p&gt;.41). Nevertheless, IgAV adult patients had significantly shorter survival time (5.5 years, 95% CI: 4.8-6.2 years) than IgAN patients (7.0 years, 95% CI: 6.6-7.5 years, p&lt;.01). Conclusion This retrospective study demonstrates that IgAV in adults presents substantial clinical manifestations, including high risk of progression to persistent renal impairment and possesses higher mortality rate in comparison with pediatric-onset disease and IgAN. References [1]Blanco R, Martínez-Taboada VM, Rodríguez-Valverde V, García-Fuentes M, González-Gay MA. Henoch-Schönlein purpura in adulthood and childhood: two different expressions of the same syndrome. Arthritis Rheum. 1997 May;40(5):859-64. doi: 10.1002/art.1780400513. PMID: 9153547. [2]Nossent J, Raymond W, Isobel Keen H, Preen D, Inderjeeth C. Morbidity and mortality in adult-onset IgA vasculitis: a long-term population-based cohort study. Rheumatology (Oxford). 2021 Dec 24;61(1):291-298. doi: 10.1093/rheumatology/keab312. PMID: 33779729. Figure 1. Disclosure of Interests None declared